Do you get confused when using handles to structs in C?
Do you miss ^^. from the days when you used Pascal?
Do you wish C had a way to dereference sequences of handles to structs left-to-right, without nested brackets?

You need sprong!

What is sprong?

Sprong is a useful trick for Macintosh C programmers.
It's a block of punctuation which looks like this:

So just what is sprong good for?

When you have a pointer to a struct, C lets you use a->b or (*a).b .
Most people use a->b as it keeps the punctuation in one block, and it nests more easily -
a->b->c is always preferred to (*(*a).b).c
That left-to-right dereferencing wins every time.

However the Macintosh normally uses Handles, not pointers, and you are forced to use the * notation, doing things like (**(**a).b).c or
(*(*a)->b)->c.

Most Mac programmers have been using this notation for a while, and the best thing you can say about it, is that you get used to it after a year or two.

The solution is to use a very useful chunk of punctuation called "sprong", which looks like this-



It is directly equivalent to ^^. in pascal, and is very useful when dealing with handles to structs. Because C treats arrays and pointers the same, a[0] is the same as *a, and a[0]->b is the same as
(**a).b or (*a)->b.

It's cool because it is easier to dereference left to right than nest loads of brackets and stars. I prefer this:

short mainDepth = GetMainDevice() [0]-> gdPMap [0]-> pixelSize;

to this:

short mainDepth = (**(**GetMainDevice()).gdpMap).pixelSize;

Doesn't [0]-> look a bit weird?

The first time you see a[0]->b[0]->c it looks a bit strange, but once you've got over the initial shock, it's really a big improvement. You can set up a keyboard macro to type [0]-> for you, and all you have to do is type identifiers, hitting the sprong key inbetween. I find it is more readable than the alternatives. It is no less clean. It generates the same code. It is just less familiar.

Also, consider the alternative - just think back to the first time you saw that nested brackets and stars notation, and how many tries it took to get the code right. Basically it sucks. You end up with loads of nested brackets all over the place, and it isn't very readable.

Try it - you'll like it.

Why is it called "sprong"?

I just liked the sound of it. It's a bit like "pling" which some people use for exclamation mark, and sprong looks a bit springy.
Ronny Wichers Schreur tells me it means "jump" in Dutch.
Maf means "a bit under the weather" in a Belgian language apparently.

Will I get strange code generated if I use sprong?

There is no reason why a[0]->b should give you different object code from (**a).b
A dereference is a dereference.

Is "sprong" Prince's new name?

No, that's more like this -

O-|->



Sprong FAQ - Maf Vosburgh <maf@goat.demon.co.uk>